repl: handle dot commands syntax error for multiline inputs

lib/repl.js

@@ -78,6 +78,7 @@ const {
   StringPrototypeIncludes,
   StringPrototypeRepeat,
   StringPrototypeSlice,
+  StringPrototypeSplit,
   StringPrototypeStartsWith,
   StringPrototypeTrim,
   Symbol,
@@ -802,11 +803,13 @@ class REPLServer extends Interface {
       }
 
       // Check REPL keywords and empty lines against a trimmed line input.
-      const trimmedCmd = StringPrototypeTrim(cmd);
+      let trimmedCmd = StringPrototypeTrim(cmd);
 
       // Check to see if a REPL keyword was used. If it returns true,
       // display next prompt and return.
       if (trimmedCmd) {
+        const splitString = StringPrototypeSplit(trimmedCmd, '\r');
+        trimmedCmd = splitString[splitString.length - 1];
         if (StringPrototypeCharAt(trimmedCmd, 0) === '.' &&
           StringPrototypeCharAt(trimmedCmd, 1) !== '.' &&
           NumberIsNaN(NumberParseFloat(trimmedCmd))) {

test/parallel/test-repl-multiline-dot-commands-execution.js

@@ -0,0 +1,47 @@
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+const { startNewREPLServer } = require('../common/repl');
+
+
+const dotCommandSyntaxError =
+  /Uncaught SyntaxError: Unexpected token '\.'/;
+
+
+function runDotCommand(command, validate) {
+  const { replServer, output } = startNewREPLServer();
+
+  replServer.on('exit', common.mustCall());
+  replServer.write(`${command}\n`);
+  replServer.write('let testObj = {\n');
+  replServer.write(`${command}:"dummy-value"\n`);
+  replServer.write(`}`);
+  replServer.write('function a() {\n');
+  replServer.write('console.log("logging");\n');
+  replServer.write(`let value = testObj ${command} \n`);
+  replServer.write('console.log(value) \n');
+  replServer.write(`${command}\n`);
+  validate(replServer, output);
+  replServer.write('arr = [1,\n');
+  replServer.write('consdole.log("logging");\n');
+  validate(replServer, output);
+  replServer.close();
+}
+
+runDotCommand('.break', common.mustCall((replServer, output) => {
+  replServer.write('1 + 1\n');
+  assert.doesNotMatch(output.accumulator, dotCommandSyntaxError);
+  assert.match(output.accumulator, /2\n/);
+}, 2));
+
+runDotCommand('.clear', common.mustCall((replServer, output) => {
+  replServer.write('1 + 1\n');
+  assert.doesNotMatch(output.accumulator, dotCommandSyntaxError);
+  assert.match(output.accumulator, /2\n/);
+}, 2));
+
+runDotCommand('.help', common.mustCall((replServer, output) => {
+  replServer.write('1 + 1\n');
+  assert.doesNotMatch(output.accumulator, dotCommandSyntaxError);
+  assert.match(output.accumulator, /2\n/);
+}, 2));